Variable throw crank



May 5, 1942.

VARIABLE THROW CRANK Original Filed Dec. 19, 1939 jml' Q Q J. c. WOODFORD 2,281,903

Patented May 5, 1942 UNITED STATES PATENT FFICE VARIABLE THROW CRANK Joseph C. Woodford, Wayne, Pa., assignor to John Wood Manufacturing Company, Inc., Conshohocken, Pa., a corporation of Delaware Original application December 19, 1939, Serial No. 309,949. Divided and this application November 4, 1940, Serial No. 364,265

5 Claims. (01. 74-602) This is a division of my co-pending applicathereof, beside said bearing, a gear which is contion Serial No. 309,949, filed December 19, 1939, centric with the axis of the crank pin and now Patent No. 2,259,052, for Improvement in meshes with a gear which is rigidly connected fluid meters. with said normally stationary shaft. Rotary ad- My invention may be conveniently utilized in F justment of said normally stationary shaft with a meter operated by the flow of liquid in any its gear efiects rotary adjustment of said eccenliquid dispensing apparatus, for instance, in distric bushing on said crank pin and in its bearpensation of lubricating oil or gasoline or other ing in the piston rod, with the effect of predefuel oil. However, the essential features of my termining and maintaining the desired length of invention may be utilized in the construction in Stroke of t piston m t Same i i d by of a fluid meter of the type disclosed in Letters adjustment f aid l ver,

Patent 0 t United St ,003, grant- My invention includes the various novel feaed June 1935, to Parker et 811-, for D tures of construction, arrangement, and method ment in piston meters. of operation hereinafter described.

This invention is an improvement upon that 15 In said drawing: Fig. I is a partly elevational disclosed in my co-pending application Serial and partly sectional view of a displacement me- NO. August 17, now Patent ter conveniently embodying my invention NO. 2,242,715, wherein Joseph E. Fernly is named Fig II is an inside elevation of t j t as a joint inventor, and relates particularly to m lever and gearing Shown in Fig L the means for securing in adjusted position 0 The form of my invention shown in this means for Varying the throw of a P Where plication differs from that in my original appliby F length of the Stroke plston may be cation in that an internal gear is substituted for varied to vary the amount mud passed through the external gear fixed on the inner end of the the piston cylinder during such stroke. In said normally Stationary Shaft Shown in the Original pending app1icatin the same application and the adjusting lever is of simpler purpose 1s a nut on a shaft which is continuousform 1y rotated during the operation of the meter. Therefore, as said nut is presented outside of the The casmg may be of any Convement form having a fluid inlet 2 and outlet 3 for the pasmeter casm n d justment it is nez es ryt tg izriziifli iafo coiir m g of .fiuld t and out of the plston (ihainber for it which must be removed to efiect any de- 4 m sald casmg The crank-shaft 5 1s Joursired adjustment for varying the throw of said naled in the healing 5 in Said .casing i crank. On the contrary, in accordance with the arm 5a carrying the eccentnc crank pm 5 sue a us on is carried b a n all ai tionary f and includes g f sleeve having a cylindrical outer surface l5 ecthe end of said normally stationary shaft eX- centric to the axls of SmdPm :1 sand bushing terior to the meter casing and having an arcuate gfi 55 22 r gga; gfi zfi 8;

slot through which extends a cap screw in en- 6 on i p e gagement with the meter casing, whereby the lem which is coiinecied with t piston by P Pivot ver and said normally stationary shaft are seso that m be ljeclproca'ted m 534d plston cured in any desired position of variance of the f g sfjlldbbushing16aha;1 at one egg thleirell throw of the crank, o esi e sai earmg e gear w c The f f my invention chosen for m meshes with the internally toothed gear I6 tration is embodied in a positive displacement which is rigidly Connected, Conveniently by a meter, wherein the crank-shaft is axially aligned p w the normally Stationary djustin Shaft with said normally stationary shaft and has rig- The We of gear is Serves as an abutidly connected therewith an eccentric crank merit to prevent axial displacement of the pin; which pin carries a bushing fitted for rocentric bushing sleeve 6 n its r 6.

tary adjustment thereon, which bushing is a As m y e n d f m he win the p h sleeve, having a cylindrical outer surface eccendiameter of the internally toothe a 16 i5 tric to the axis of the pin. Said bushing extwice the pitch diameter of the gear 6 which tends through a bearing in one end of a connectes es W h d gear ThuS, each time the ing rod, the opposite end of which is pivoted in gear 6 travels a complete revolution of 360 the piston, and said bushing has at one end withinsaicl gear IS, the piston of the meter is moved through one complete stroke and returned to initial position.

The adjusting lever I1, is directly engaged by its keyJ'l with the normally stationary adjusting shaft l and held on the latter by the nut l8. As shown in Fig. II; said adjusting lever I! has the arcuate slot I1 in coaxial relation with said shaft l0. Said lever i! may be locked in adjusted position by the lock screw 19 which extends through said slot I l into the casing l, as shown in Fig. I. In that form of my invention; the sealing washer 20 interposed between the hub of the internal gear [6 and the bearing of the shaft Ill in the casing l is substituted for the packing with the screw threaded gland shown in the original application.

When the adjusting lever I1 is in the position shown in full lines in Fig. II, the eccentric bushing 6 is in position to afford the maximum length of stroke of the piston rod I and piston 8, but, when said lever is adjusted to the position-shown in dash lines in Fig. II, said eccentric bushing is adjusted to the position affording the minimum length of stroke of rod 1 and piston 8.

However, I do not desire to limit myself to the precise details of construction, arrangement, or method of operation-herein set forth, as it is obvious that various modifications may be made therein without departing from the essential features of my invention as defined in the appended claims.

I claim:

1. In a positive displacement fluid meter having a casing containing a piston cylinder and a piston mounted to reciprocate in said cylinder; the combination with a crank-shaft having an eccentric pin for effecting reciprocation of said piston; of an eccentric bushing sleeve mounted to be turned on said pin and having a cylindrical outer surface in eccentric relation to the axis of said pin; a piston rod pivotally connected with said piston and with said bushing sleeve; an externally toothed gear on one end of said bushing sleeve in concentric relation with the axis of said crank pin; a normally stationary shaft having an internally toothed gear rigidly mounted thereon and in mesh with said first gear; a web on said internally toothed gear; means at the outer end of said normally stationary shaft for turning it and thereby varying the eccentricity of the axis of said bushing sleeve with respect to the axis of said crank-shaft; and means for securing said normally stationary shaft in adjusted position in rigid relation with said casing.

2. A structure as in claim 1; wherein the means at the outer end of the normally stationary shaft for turning it is a lever, having means holding it in rigid relation with said shaft.

3. A structure as in claim 1; wherein the means at the outer end of the normally stationary shaft for turning it is a lever, having means holding it in rigid relation with said shaft; and the means for securing said shaft in adjusted position in rigid relation with the casing, includes a lock screw in threaded engagement with the casing and extending through an armate slot in th lever.

4. A structure as in claim 1; wherein the normally stationary shaft is in coaxial relation with the crank shaft and internal gear; so that rotation of the crank shaft circularly progresses the bushing sleeve gear in mesh with the internal gear and consequently varies the position of the eccentric bushing on the crank pin, but the pitch diameter of the bushing gear is in such aliquot relation to the pitch diameter of the internal gear that the bushing sleeve is in such position at the discharge end of the stroke of the piston to produce the desired displacement by the piston, indicated by the external setting.

5. A structur as in claim 1; wherein the normally stationary shaft is in coaxial relation with the crank shaft and the pitch diameter of the bushing sleeve gear is one-half that of the internal gear in mesh therewith; whereby the bushing sleeve is in such position at the discharge end of the stroke of the piston to produce the desired displacement by the piston, indicated by the external setting.

JOSEPH C. WOODFORD. 

